Expensive treatments for common conditions are unaffordable for most health system, even if they are cost effective. Julian Urrutia and colleagues examine how countries could respond to WHO making direct acting antivirals essential medicines

New direct acting antiviral drugs to treat hepatitis C infection are highly effective. Sofosbuvir and velpatasvir have been shown to achieve 90-100% cure rates regardless of hepatitis C virus (HCV) genotype.1 They are also very expensive, commanding list prices that can exceed $1000 (£700; €880) a day. Nevertheless, studies have shown that treating everyone infected with HCV in the United States is cost effective from a societal perspective.2 Moreover, manufacturers are already offering substantial discounts. Advocates are thus demanding that these drugs should be made available for everyone infected with HCV.134 The World Health Organization (WHO) recently added sofosbuvir, along with other highly expensive medicines, to its model list of essential medicines.56 However, HCV infection is so common that covering these drugs for all who might benefit is not a realistic option for most health systems, even if the price were $1 per pill, which is the estimated minimum cost of production,78 rather than $1000. So how should countries respond?

Essential medicines and priority setting

Inclusion on the list does not mean that every country should guarantee access to everyone who might benefit, regardless of cost. WHO defines essential medicines as “those that satisfy the priority healthcare needs of the population.” Yet the agency also notes that “essential medicines are intended to be available … at a price that the individual and the community can afford,” adding that the list is not designed to be a global standard but a “guide for the development of national and institutional essential medicine lists” (box 1).910 This intentional ambiguity leaves room for countries …